An improved permanent‐magnet synchronous machine sensorless drive based on the fuzzy‐PI phase‐locked loop and the adjustable boundary‐layer FOSMO

Abstract

This study proposes a variable boundary-layer full-order sliding-mode observer (FOSMO) with a fuzzy proportional plus integral (PI) phase-locked loop (PLL) for the sensorless control of a permanent-magnet synchronous machine (PMSM). The sigmoid switching function-based FOSMO, which includes feedback speed information, is presented and considered as the conventional method. To address the contradiction between the convergence performance and the chatter-reduction ability of the sliding-mode control, a fuzzy logic controller (FLC) is introduced to adjust the boundary-layer thickness according to the estimation error. Furthermore, a real-time parameter tuning module is integrated into the PI regulator of the conventional PLL to adjust its noise bandwidth. Hence, adverse effects of disturbance and external noise, especially under transient operations, can be eliminated. An overall PMSM sensorless field-oriented control scheme incorporating the proposed method is designed, and the corresponding experimental platform is constructed. Several groups of comparative experiments reveal that system chatters are largely reduced using the proposed method under both of the high-and low-speed running conditions and the dynamic anti-interference performance can also be significantly improved under load and speed disturbances. Therefore, the feasibility and effectiveness of the proposed variable boundary-layer FOSMO + fuzzy-PI PLL method are validated.

Variable step control to improve scanning speed of gene sequencing stage

“…Where v E is the electric speed of the motor; ψ f is the permanent magnet flux linkage; L d and L q are the d -axis and q -axis coil inductance respectively, and L d ≈ L q = L for surface-mounted PMSM. The transfer function of the current-electromagnetic force transformation in the linear range can be obtained as follows 19 :…”

Adaptive control schemes based on characteristic model for servo motor drives

“…In [7], a two-degree-of-freedom proportional-integral (PI) controller is proposed to improve inertia disturbance suppression with a disturbance observer. In [8], a real-time parameter tuning module is integrated into the PI regulator of the conventional phase-locked loop (PLL) to adjust its noise bandwidth. These improvements are effective in certain applications, but they still encounter a relatively poor disturbance rejection performance which causes problems in high dynamic applications such as in industrial servo drives.…”